Intermittent-absorption-refrigeration apparatus



Oct. 21, 1930. Q5 LUNDBERG 1,779,070

INTERMITTENT ABSORPTION REFRIGERATION APPARATUS Filed March 10, 1928 I n we: 1'0;- Cnn EMANUE Zwvnasza I ATTORIVE Y Patented Oct. 21, 1930 CARL EMANUEL runner-me, or STOCKHOLM, SWEDEN INTERMITTENT-ABSORPTION-REFRIGERATION APPARATUS Application filed March 10, 1928, Serial No.

The present invention relates to an arrangement in intermittently Working refrlgerators of the absorption type, in which the boiler also serves as. an absorber, and the purpose of the invention is to effect an apparatus of reliable working, which automatlcally tends to return the absorption fluid to the boiler if for instance'such a fluid has entered the evaporator. Such an entering of absorption fluid to the evaporator may take place if the condensation is not sufiieient or if the apparatus is exposed to careless treatment, for instance a tilting, which may easily occur when transporting the apparatus.

According to the'present invention the objection is removed by the fact that the bottom part of the boiler tapers 1n the downward direction and that the, conduit arranged between the evaporator and the holler and adapted to return the cooling-means to i the boiler opens into the boiler at tapering bottom part thereof, so that a very small quantity of fluid in the boiler will be suflicient to allow the mouth of the conduit opening into the boiler to extend below the surface of the fluid.

The invention relates to such ashaping of the boiler that the gas expelled from the absorption fluid will. be forced, in an efiicient manner, to flow ofl to the condenser and from this to the evaporator. This eflect is obtained by the fact that the top part of the boiler tapers, conically, in an upward direction, and that the outlet pipe for the gas expelled from the fluid contained in the boiler issues from the highest point of the boiler.

Other features characteristic of the invention will be more. particularly set forth in connection withthe description of the embodiments shown in the annexed drawing.

Fig. l'shows a refrigerator of the absorption type carried out according to the invention in vertical, longitudinal section and Fig. 2 shows a somewhat modified embodiment 4 of the evaporator.

The boiler absorber 1 has a cone-shaped top and an inverted cone-shaped bottom, while 2 is the condenser and 3 the evaporator which is likewise shaped as a double cone. .The

boiler-absorber contains a heating-device 4,

, preferably 260,646, and in, Sweden January 27, 1e2s.

an electric heater, and a coolingwater coil 5, which is supplied with cooling water during-the absorption period through a cock 6 arranged in the outlet pipe 7 of the condenser 2.

The boiler-absorber 1 although it has the same shape as the evaporator 3 has however a greater volume thansaid evaporator. The result of this greater volume is that a minimum liquid level will always be maintained within said boiler-absorber One particular advantage of maintaining this minimum level is that the heater. 4 will always be covered with liquid thereby reducing any possibility of its burning out. I

*At the apex of the cone-shaped top of the boiler-absorber is'a pipe 8 adapted to lead the gas, expelled from the absorption fluid during the boiling period to the condenser 2 and thence to the evaporator 3. A return pipe 9 leads from the evaporator 3 to a point below the minimum liquid level in the boilerabsorber 1, thus ensuring that the upper end of said return pipe will not be unsealed to destroy its siphon like action; The return pipe is, in the embodiment shown in the drawing, divided into a number of small branches 10 at the end located in the evaporator, and v a gas return tube 11 opens at or somewhat above the opening points, of said pipes, in said return pipe 9. The free end ofsaid tube 11 opens near the top of the evaporator.

A drain pipe 12 leads froma point below the minimum liquid level in the boiler-absorber 1 into pipe 8 in such a manner that any absorption fluid which is vaporized and passes into pipe 8 will be condensed and returned to the boiler-absorber by means of said pipe 12. Reintroducing the condensed absorption fluid at a point below the minimum li uid level ensures that the gas being driven o of said absorption fluid will be as dry as possible. I

Assuming that the absorption fluid in boiler evaporator 1 is water and that said 95 fluid is saturated with a gas suchias ammonia and that the heating period of the cycle is beginning, the operation of this device will be as follows: y

During boiling, at which time the coolingthe cock 6 is opened, so that cooling-fluid may i now flow through the cooling pipe '5. The condensed gas in the evaporator is gasified, at the same time absorbing heat, and the gas produced escapes through gas return tube 11 and the conduit 9 to the boiler-absorber Where the gas is absorbed in the absorption fluid being cooled by the cooling-pipe 5. When all fluid is gasified in the evaporator,

"the electric heater 4 will again be heated and the cycle repeated.

If, for any reason, absorption fluid has entered into the evaporator'this fact will, of course, cause a reduction of the efiiciency of the refrigerator. According to the present invention such fluid entering into the evaporator may, however, be returned, in an automatic way, to the boiler; This fluid, which, on account of its relatively high specific weight accumulates at the bottom of the evaporator, may be carried ofl" from the evaporator through the pipes 10, 9 when the charging of the evaporator with condensed liquid has attained such a point that the fluid level in the evaporator is higher than shown in Fig. 1 of the drawing, that is to say, above the opening of the pipe 11 into the pipe 9. en this takes place, gas produced in the evaporator, cannot escape through the pipe 11, this latter forming a water-seal, and the pressure prevailing in the evaporator, will rise so as to cause the absorption fluid located at the bottom part of the evaporator to be forced up through the pipes 10, 9 and re turned to the boiler. This flowing operation is facilitated by the fact that the boiler, at this moment, 'acts as an absorber vsince the cooling has created a certain under-pressure. After a certain amount of fluid has been transferred to the boiler from the bottom part of the evaporator, the fluid level in the evaporator has fallen so that the end of piping 11 will emerge from the fluid, and the trans erring of fluid from the evaporator to the boiler will cease. The evaporator will thenbegin its normal work effecting the cooling in the way described above.

In order to prevent the fluid from being pressed back to the boiler through the pipe 8, this latter may be placed on a higher level than the pipe 9 and may, besides, be provided with contractions or other obstacles, for instance a number of funnel-shaped plates 14, shown in Fig. 2, appropriate to counteract such a flowing-back.

a pipe leading said boiler-absorber to the lower Having now particularly described the nature of my invention and the manner of its operation, what I claim is:

refrigerating apparatus of the absorption type comprising a boiler-absorber aving a cone-shaped top and inverted coneshaped bottom, an evaporator having a similar shape and less volume to maintain the minimum liquid level in said boiler-absorber, from the apex of the top of portion of means positioned within said pi e" to deter the upward movement of liquid rom said evaporator, a condenser surrounding said pipe, a return pipe leading from the lower portion of said evaporator said evaporator,

into said boiler-absorber below the minimum liquid level thereof, and a gas return tube connected to said return pipe above the lower end thereof, the other end of said gas return tube being in the upper. portion of said evaporator.

2. A refrigerating apparatus of the absorption type comprising a boiler-absorber having a cone-shaped top and inverted coneshaped bottom, an evaporator having a similar shapeand less volume to maintain a minimum liquid level in said boiler-absorber, a pipe leadin from the apex of the top of said boiler-absor er to said evaporator, a condenser surrounding said pipe, a return pipe having a plurality of small branches adjacent the lower portion of said evaporator leading therefrom into said boiler-absorber below the minimum liquid level thereof and having a gas return tube connected thereto above the junction of said branches, the other end of said gas return tube being in the upper portion of said evaporator.

3. A refrigerating apparatus of the absorption type comprising a boiler-absorber having a cone-shaped top and inverted coneshaped bottom, an evaporator having a similar shape and less volume to maintain a minimum liquid level in said boiler-absorber, a pipe leading from the apex. of thetop of said boiler-absorber to the lower portion of said evaporator, means positioned within said pipe to deter upward movement of the fluid of said'evaporator comprising a plurality of inverted truncated cones integral with the walls of said pipe, a condenser surrounding said pipe, a dram pipe partially within said pipe and having its lower end below the minimum liquid level'of said boiler-absorber,

a heater in said boiler-absorber below said minimum liquid level, a return pipe having a plurality of small branches adjacent the lower portion of said evaporator leading therefrom into saidboiler-absorber below the minimum liquidlevel thereof and a gas return tube connected to said return pipe, the other end of said gas return tube being in the upper ortion of said evaporator.

ARL EMANUEL LUNDBERG. 

